#include<cstdio>
#include<cstring>
using namespace std;
int f[105][105];
int a[105][105];
int r,c;
int longest(int x,int y);
int maxlong=-1000;
int main()
{
	scanf("%d%d",&r,&c);
	for (int i=1;i<=r;i++)
	{
		for (int j=1;j<=c;j++)
		{
			scanf("%d",&a[i][j]);
		}
	}
	memset(f,-1,sizeof(f));
	for (int i=1;i<=r;i++)
	{
		for (int j=1;j<=c;j++)
		{
			int tmp=longest(i,j);
			maxlong=maxlong>tmp?maxlong:tmp;
		}
	}
	printf("%d",maxlong);
	return 0;
}
int longest(int x,int y)
{
	if (f[x][y]<0)
	{
		int maxlen=0;
		if (x>1 && a[x][y]>a[x-1][y])
		{
			int clen=longest(x-1,y);
			if (maxlen<clen)
				maxlen=clen;
		}
		if (y>1 && a[x][y]>a[x][y-1])
		{
			int clen=longest(x,y-1);
			if (maxlen<clen)
				maxlen=clen;
		}
		if (x<c && a[x][y]>a[x+1][y])
		{
			int clen=longest(x+1,y);
			if (maxlen<clen)
				maxlen=clen;
		}
		if (y<r && a[x][y]>a[x][y+1])
		{
			int clen=longest(x,y+1);
			if (maxlen<clen)
				maxlen=clen;
		}
		f[x][y]=maxlen+1;
	}
	return f[x][y];
}